1. Field of the Invention
This invention relates to controlling ignition timing for an internal combustion engine.
2. Prior Art
Various means are known for controlling the ignition spark timing in an internal combustion engine. For example, spark can be determined by mechanical apparatus as a function of engine speed. Also known are various electronic calculation means wherein a computer processes various inputs defining engine operating parameters to produce a desired timing for operation of the ignition system.
U.S. Pat. No. 4,018,202 issued to Gartner teaches an adaptive engine dwell. U.S. Pat. No. 4,367,722 issued to Tiaki Mizuno has similar teachings. U.S. Pat. No. 4,380,989 issued to Twao Takaki adapts a primary current level in response to secondary energy calculation integrating secondary voltage and current. U.S. Pat. No. 4,446,843 to Rumbaugh teaches an adaptive dwell with a constant percent of excess dwell. U.S. Pat. No. 4,649,888 issued to Matoshi Kawai teaches an adaptive dwell ignition system. U.S. Pat. No. 4,711,226 to Neuhalfen teaches dwell energy control. However, none of the aforementioned patents teach adaptive ignition switching delay compensation for more accurate spark timing using feedback of secondary winding voltage, as reflected back to the primary winding, for improved spark timing.
It would be desirable to have an adaptive ignition switching delay compensation for more accurate spark timing. In particular, it would be desirable to take advantage of feedback of secondary voltage reflected to the primary for improved spark timing. These are some of the problems this invention overcomes.